syms x w u v
f =cos(x)*exp(-x^3); D1 = fourier(f) 
g = log(abs(w)); D2 = fourier(g) 
h = x*exp(-abs(x)); D3 = fourier(h,u) 
syms x real
k = sinh(-x^2*abs(v))*cosh(u)/v
D4 = fourier(k,v,u)
